DOCUMENTATION:
  name: ternary
  author: Brian Coca (@bcoca)
  version_added: '1.9'
  short_description: Ternary operation filter
  description:
    - Return the first value if the input is C(True), the second if C(False).
  positional: true_val, false_val
  options:
    _input:
      description: A boolean expression, must evaluate to C(True) or C(False).
      type: bool
      required: true
    true_val:
      description: Value to return if the input is C(True).
      type: any
      required: true
    false_val:
      description: Value to return if the input is C(False).
      type: any
    none_val:
      description: Value to return if the input is C(None). If not set, C(None) will be treated as C(False).
      type: any
      version_added: '2.8'
  notes:
    - Vars as values are evaluated even when not returned. This is due to them being evaluated before being passed into the filter.

EXAMPLES: |
  # set first 10 volumes rw, rest as dp
  volume_mode: "{{ (item|int < 11)|ternary('rw', 'dp') }}"

  # choose correct vpc subnet id, note that vars as values are evaluated even if not returned
  vpc_subnet_id: "{{ (ec2_subnet_type == 'public') | ternary(ec2_vpc_public_subnet_id, ec2_vpc_private_subnet_id) }}"

  - name: service-foo, use systemd module unless upstart is present, then use old service module
    service:
      state: restarted
      enabled: yes
      use: "{{ (ansible_service_mgr == 'upstart') | ternary('service', 'systemd') }}"

RETURN:
  _value:
    description: The value indicated by the input.
    type: any